Case IH 3886 – Engine ECU: DPF Intake Temperature Higher Than 700 deg C

This code indicates that the exhaust gas temperature entering the Diesel Particulate Filter (DPF) has exceeded the safe operational threshold of 700°C (1292°F). The extreme temperature can be caused by an actual over-temperature event during an active regeneration cycle, an over-fueling issue in the aftertreatment burner, or a skewed/faulty temperature sensor giving a false high reading.

• skid steer
• Small and Medium Frame Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)
• SR130
• SR160
• SR175
• SV185

1. 1

   Verify Sensor Accuracy: Use the Case IH Electronic Service Tool (EST) to monitor the DPF Intake Temperature Sensor live data. If the sensor reads >700°C when the engine is cold, the sensor or its wiring is faulty.

2. 2

   Check for Related Codes: Look for associated electrical codes. For example, Code 3175 ("DPF Intake Temperature Sensor Low Voltage") indicates a short to ground or sensor failure rather than an actual thermal event. Look for burner injector codes (e.g., 3989 or 3990) which could indicate the external burner is dumping too much fuel and causing a genuine over-temperature condition.

3. 3

   Inspect Wiring and Connectors: Check the wiring harness leading to the DPF Intake Temperature Sensor for chafing, melted insulation, or loose pins.

4. 4

   Inspect the Aftertreatment Burner: Since the ISM-IDI engine uses an external burner for regeneration, inspect the burner nozzle and air pump for malfunctions that could cause uncontrolled burning.

5. 5

   Inspect the DOC/DPF: Check the Diesel Oxidation Catalyst (DOC) and DPF for face plugging, excessive soot accumulation, or signs of thermal damage (discoloration of the metal housing).

1. 1

   Safety First

   Turn off the machine, disconnect the battery, and allow the exhaust system to cool completely. The DPF and surrounding components operate at extremely high temperatures.

2. 2

   Locate the Sensor

   Locate the DPF Intake Temperature Sensor, which is threaded into the exhaust piping between the DOC outlet and the DPF inlet.

3. 3

   Disconnect Wiring

   Carefully unplug the sensor's electrical connector from the main engine harness.

4. 4

   Remove the Sensor

   Apply penetrating oil to the sensor threads if it is seized. Use a specialized sensor socket or a flare-nut wrench to carefully unthread the sensor from the exhaust pipe to avoid stripping the threads.

5. 5

   Install the New Sensor

   Apply a small amount of high-temperature anti-seize to the threads of the new sensor (if not pre-applied by the manufacturer). Thread it in by hand, then tighten to the OEM torque specification.

6. 6

   Reconnect and Clear Codes

   Reconnect the electrical harness. Reconnect the battery, connect the EST diagnostic tool, and clear the inactive 3886 fault code.

7. 7

   Validation

   Start the engine and monitor the DPF Intake Temperature live data. Perform a forced stationary DPF regeneration to ensure the burner ignites properly and the intake temperature remains within the normal operating range (below 700°C) without triggering the code.